TEWI-Kolloquien „Semantische Systeme“, 10.-11. April 2017

Montag, 10. April 2017, E.1.42

8:30 – 9:30, Christoph BENZMÜLLER

Title: Calculemus! Progress in Universal Logic Reasoning and Computational Metaphysics

Abstract: Inspired by Leibniz‘ famous vision „Calculemus! — Let us calculate“, an approach to universal logic reasoning is presented. The proposed solution is indirect: it utilises classical higher-order logic as a universal meta-logic in which various other (classical and non-classical) logics from today’s logic zoo can be shallowly embedded and combined; the embedded (object-)logics can then be employed for the representation of knowledge in different application domains.

This semantical embedding approach suppor ts the formalisation and deep logical assessment of rational arguments on the computer. In this sense, it partially realises Leibniz‘ dream. To illustrate this, I will present a rigorous analysis of modern variants of the “Ontological Argument for the Existence of God“, including Kurt Gödel’s seminal contribution. By utilising the approach, even relevant new insights about the ontological argument have recently been revealed by automated theorem provers. These research activities have inspired the conception of a new, awarded lecture course on “Computational Metaphysics“ at Freie Universität Berlin, which brings together students from computer science, mathematics and philosophy.

The approach, which fruitfully combines and exploits, amongst others, own research contributions from the last two decades, is by no means  restricted to metaphysics or philosophy; this is evidenced by recent applications e.g. in mathematics and artificial intelligence.

11:00 – 12:00, Wolfgang FABER

Titel: Deklarative Formalismen als Motoren Semantischer Systeme

Abstract: Semantik in Wissensbasierten System ist der Schlüssel, um über das vorhandene Wissen selbst Schlüsse zu ziehen. Semantik kommt besonderer Bedeutung zu, wenn nicht nur Antworten oder Lösungen gefunden werden sollen, sondern auch Begründungen oder Erklärungen selbiger. In diesem Vortrag soll die Rolle deklarativer Formalismen (im Sinne deklarativer Sprachen und Systeme) in solchen Semantischen Systemen herausgearbeitet werden. Besondere Berücksichtigung werden dabei logische Programmierung und Regelsysteme finden.

14:30 – 15:30, Martin GEBSER

Titel: Knowledge Representation and Reasoning in Practice

Abstract: Modern computing systems provide tremendous resources to automate sophisticated calculations, as required in various application areas, including life sciences, machine learning, planning and scheduling, product configuration, system synthesis and verification, etc. This goes along with an increasing demand for expressive, general-purpose means for knowledge representation and reasoning. In my talk, I outline how computational logic along with extensions can serve as a powerful paradigm for representing and solving demanding real-world applications by means of general, domain-independent search and optimization methods.


Dienstag, 11. April 2017, E.1.42

8:30 – 9:30, Jörg HOFFMANN

Titel: Automatic Planning: Some Recent Methods and Applications

Abstract: Automatic Planning is one of the founding areas of Artificial Intelligence, concerned with the automation of problem solving: the design of algorithms whose input is a declarative problem description („the rules of the game“) and that automatically find a solution („the game strategy“) to any such input. The curse of generality is complexity — even the simplest planning problems are PSPACE-complete to solve, in the size of the declarative description — so effective search methods are paramount. After a brief introduction to the area, the talk summarizes two such methods developed in recent work by the author, namely star-topology decomposition which breaks conditional dependencies among components in the input; and conflict-based learning which learns sound and generalizable knowledge from dead-end states encountered during forward state space search. We then highlight a recent application of planning techniques, to simulated network penetration testing in IT security. We conclude with an outlook on future challenges.

11:00 – 12:00, Stefan EDELKAMP

Title: Multi-Goal Motion Planning

Abstract: In the clothes of vehicle routing, multi-goal task planning has been an apparent optimization question for a fairly long time. We will present advances in high-speed solving these discrete planning problems. With fast single-source shortest path planning, the in- or outdoor map for the vehicle fleet is condensed to a graph of customer orders, which could be any combination of pickups and deliveries.  For one vehicle this setting corresponds to a variant of the NP-hard traveling salesman problem with capacities and time windows, while for several vehicles and according to the dynamics in the orders within a multi-agent simulation system, we support negotiating agents that offer multi-modal transport services.

While the discrete multi-goal task planning problem is already hard, the integration of task and motion planning is considered to be one of the most important challenges to nowadays robotics. Robots have sizes, heading, and velocity, and their motion can often be described only according to non-linear differential equations. The dynamics of movements, existing obstacles and many waypoints to visit are only some of the challenges to face. In real-world problems, we often have additional constraints like inspecting areas of interest in some certain order, while still minimizing the time for the travel. The trickiest part is to solve the hard combinatorial discrete tasks like the generalized and clustered traveling salesman problems, and -at the same time- providing valid trajectories for the robot. We use a framework in which a motion tree is steadily grown, and abstractions to discrete planning problems are used as a heuristic guidance for the on-going solution process to eventually visit all waypoints. In case of inspection, we generate the waypoints fully automatically, using a combination of 2D and 3D skeletonization together with a filtering mechanism based on hitting sets.

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A Behavior-based Approach to Secure and Resilient Industrial Control Systems

Dr. Dimitrios Serpanos | March 9, 2017 | 12:30 | E.2.37


Industrial control systems (ICS) control and manage a significant portion of critical infrastructure. As cyberattacks increasingly target critical infrastructure, ICS security and resilience are required to avoid catastrophic events that may lead even to loss of life. Importantly, ICS differ from traditional IT systems in several ways, from interacting with physical processes to requirements for continuous operation and real-time processing.

In this talk, we present a behavior-based approach to the design of secure and resilient industrial control systems. Starting with a programmable specification of a control process, we develop executable code with specified security properties. A run-time middleware, ARMET, monitors the execution of the program, identifying behavioral deviations due to intrusions or process failures and leading to diagnosis and system recovery. Importantly, our approach includes a novel method for vulnerability analysis of processes.

DimitriDimitrios Serpanos is Professor of Electrical and Computer Engineering, University of Patras and Director of the Industrial Systems Institute in Greece. He has worked at IBM Research, on the faculties of the University of Crete and the University of Patras, as Principal Scientist at QCRI, as President of the University of Western Greece, and has served another term as Director of the Industrial Systems Institute. He holds a Ph.D. in Computer Science from Princeton University. His research is in embedded systems, industrial systems and security.
Professor Serpanos has co-authored several books and published research work extensively. His research has been funded by both the European Commission, the Greek Government and industry in the EU and the USA.

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TEWI Colloquia in Distributed Systems, February 20-21, 2017

Monday, February 20, 2017, E.1.05

8.30am, Dr. Andreas Mauthe, Lancaster University, School of Computing and Communications

Title: Resilience in Dynamic, Opportunistic Systems-of-Systems

Abstract: Distributed computing environments nowadays are becoming increasingly diverse and differentiated in nature. They are moving from traditional distributed systems comprising PCs/mobiles + IP networks to ecosystems that include Internet of Things (IoT) installations (e. g. smart cities and buildings), environmental sensor and actuator networks (e. g. WSNs) using non-IP protocols, cluster-based cloud systems, ad-hoc networks such as MANETs and VANETs, and virtualised systems supported by network overlays (e. g. Clouds). In order to exploit the full potential of these various „systems“ they need to be dynamically interconnected, so they can interact with, and respond to each other. For example, VANETs talk to smart cities, WSNs process data in back-end clouds, and overlay-based systems adjust their resilience properties when their underlying IP environment changes. It is becoming recognised in many research communities that this can be best achieved through a „systems-of-systems“ approach. However, this also requires a new approach towards system resilience and security considering the autonomic characteristics and dynamic nature of systems-to-systems approach. We have developed a programming approach called tecton, which is a distributed representation of a potentially-opportunistically-interacting distributed system. It provides support for opportunistic, rule-based interaction with low overhead.

In this presentation I will introduce the tecton abstraction, and in particular discuss how resilience can be ensured within a dynamic systems-of-systems ecosystem. The resilience mechanisms are based on D²R²+DR framework originally conceived within an autonomic networking concept. Resilience is provided through structural means but also active components call Resilience Managers. Through these, independent systems can interact while ensuring that security and resilience are maintained. A central component of this framework is anomaly detection that operates in conjunction with remediation to provide operational resilience considering the environmental dynamics as well as novel threats.

The talk will also provide and outlook on further research challenges in the context of critical systems infrastructure, Internet of Things (IoT) and Cyber Physical Systems. Further, it will outline how the research relates to teaching and collaborative research opportunities within AAU.


10:45am, Dr. Stefan Schulte, TU Wien, Fakultät für Informatik

Title: Elastic Computing

Abstract: Especially in volatile IT environments, there is a constant necessity to adapt computational resources to fulfil the resource and quality demands of service users. Permanently providing resources which are able to handle peak loads is not the best solution for this, as these capacities will not be fully utilized most of the time, leading to unnecessary cost. However, permanent underprovisioning of computational resources is obviously also not an option.

Within this talk, elastic computing will be discussed as a solution to satisfy volatile demands for computational resources. A special focus will be on elastic processes and elastic stream processing. Also, a brief outlook on how Internet of Things devices could be used to provide computational resources for services will be given.


2:00pm, Dr. Vlado Handziski, TU Berlin / TU Dresden

Title: The Ever-changing Landscape of Distributed Systems

Abstract: During the last two decades the distributed systems research had to constantly adapt to a rapidly changing technological landscape bringing novel challenges and questioning long-held assumptions. The talk will provide a brief overview of this evolution, focusing on several important paradigm shifts like the emergence of resource-constrained wireless devices with rich sensing and actuation capabilities, the rise of the smartphone platform, the cloud-centric architecture and big-data processing frameworks, the microservices model and the renewed interest in data-centric middleware. I will elaborate on the major milestones as part of this evolution and highlight some of my own contributions to the field. In the final part of the talk I will concentrate on the future of distributed systems and explore some novel challenges from new application fields (e.g. cyber-physical systems), new technologies (e.g. blockchains) and new algorithms (e.g. deep learning).


4:15pm, Dr. Thomas Zinner, Universität Würzburg, Institute für Informatik

Title: SDN, NFV & DASH: Leistungsbewertung neuer Mechanismen zur Netz- und Anwendungs­steuerung

Abstract: Das heutige Internet hat sich über Jahrzehnte zu einer globalen, universalen Kommunikations- und Diensteplattform entwickelt. Der Erfolg des Internets wird vor allem vorangetrieben durch das vielfältige Angebot an Anwendungen, einhergehend mit der steigenden Verbreitung durch immer schnelleren Breitband-Internetzugang.  Leider kommt es aufgrund der starren Architektur, fehlender Flexibilität, und mangelnder Ressourcensteuerung immer wieder zu Beeinträchtigung der Dienstqualität und damit der vom Nutzer wahrgenommenen Dienstgüte. Neue Technologien und Konzepte wie Cloud Computing, Software Defined Networking oder die Virtualisierung von Netzfunktionen ermöglichen eine Flexibilisierung der Kommunikationsarchitektur und damit die Überwindung dieser Nachteile.

Der Vortrag befasst sich mit Leistungsuntersuchungen neuartiger Mechanismen zur Netz- und Anwendungssteuerung, die sich durch diese Technologien ergeben.


Tuesday, February 21, 2017, E.1.05

8:30am, Dr. Radu Prodan, Universität Innsbruck, Institut für Informatik

Title: Multi-objective Modelling and Optimization of Scientific and Industrial Applications on Distributed Computing Infrastructures

Abstract: The presentation is structured in four parts. It starts with an overview of the current research conducted by the applicant at the University of Innsbruck in the field of distributed and parallel systems. The second part introduces the ASKALON environment, the main research product of the applicant, designed to simplify and support the development cycle of scientific applications on distributed computing infrastructures. Afterwards, it presents a selection of the latest research methods and results obtained in two important areas: modelling, prediction and simulation of energy consumption and multi-objective optimisation and scheduling of scientific applications on distributed computed infrastructures with respect to time, cost, energy, robustness and storage as simultaneous conflicting objectives. The third part of the talk presents the research conducted by the applicant in the area of industrial applications, with focus on massively multiplayer online gaming on distributed computing resources. The talk concludes with an outlook into the future research plans.


10:45am, Dr. Karin Anna Hummel, Universität Linz, Department of Telecooperation

Title: The Interplay of Physical Mobility and Wireless Networked Systems

Abstract: Physical device mobility challenges networked systems as it causes degraded quality of wireless communication links, disconnections, and mobility management overhead, e.g. in the cellular network. The effects of physical mobility are on the one hand observable in the network, on the other hand, mobility context can be exploited to improve networking. In this talk, I explain the relation between physical mobility and networked systems and present two lines of my recent research. In the first part, I focus on the question whether the cellular network can be used as a reliable ubiquitous sensor of physical mobility. As the observation of signaling caused by mobile devices comes with considerable spatial uncertainties, characterizing mobility is challenging. I present a robust method that allows to counteract these uncertainties for vehicular traffic estimation. The outcomes of a one-month study based on real cellular data on a European highway reveal that our method can detect road congestion episodes reliably, and even faster than methods based on traditional road observation technologies. In the second part, I discuss how delay-tolerant networks can take smarter packet forwarding decisions about when, where, and to whom to transmit by being aware of the devices’ mobility context. In this frame, I detail results of several experimental studies with our fleet of micro aerial vehicles and demonstrate that leveraging mobility information and moreover anticipating mobility characteristics improves single link transmissions and data forwarding performance over multiple links.


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Industrial Robot Security

DI Dr. Bernhard Dieber | 13.12.2016 | 14:00 Uhr | E.1.42


Die immer stärker werdende Vernetzung industrieller Systeme im Sinne der Industrie 4.0 erfordert neue Sicherheitsmaßnahmen für die eingesetzten industriellen Kontrollsysteme. Während bisher Airgaps als ausreichend empfunden wurden, werden in Zukunft IT-Security Prinzipien zum Einsatz kommen müssen. Dies ist aber in den langlebigen Industrieanlagen nicht einfach umsetzbar. Vor allem die kommende Generation an kollaborativen Robotern ist hier speziell verwundbar. In diesem Vortrag werden Probleme bei industrieller Security mit Fokus auf Robotersysteme aufgearbeitet sowie das populäre Software Framework ROS und seine Sicherheitsproblematiken näher betrachtet.

FotoBernhardDieberBernhard Dieber ist seit 2015 am Institut für Robotik und Mechatronik der JOANNEUM RESEARCH Forschungsgesellschaft mbH beschäftigt und leitet seit Juli 2016 die neu gegründete Forschungsgruppe „Robotik Systeme“. Bernhard Dieber verfügt über eine mehr als 10 jährige Erfahrung in den Bereichen Software Engineering, Sensor Networks und Smart Cameras. Die Forschungsinteressen von Dr. Dieber umfassen Software- und Systems-Engineering für robotische Systeme, Systemsicherheit und Sicherheits-Architekturen in Produktionssystemen und die Zuverlässigkeit von Robotersystemen. Arbeiten zu Themenstellungen in Bezug auf eingebettete, verteilte und Echtzeit-Systeme sowie Software-Qualität robotischer Software runden seine wissenschaftliche Tätigkeit anwendungsorientiert ab.

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TEWI Colloquia in Information Systems, 24./25. November 2016

24. November 2016, Lakeside, Raum L 1.014

09:00-11.00, Martin Atzmüller

Title: Data Analytics in Social and Ubiquitous Knowledge Spaces

Abstract: In the age of digital transformation, information and data is becoming ubiquitous. Social Media, Web 2.0, mobile and ubiquitous computing, as well as Industry 4.0 and smart production enable diverse options for the analysis and mining of the emerging complex knowledge spaces. The talk presents according approaches and methods for comprehensive analytics of the respective information and knowledge processes.

11:00-13:00, Patrick Delfmann

Title: Comprehensible Predictive Models for Business Processes

Abstract: Predictive modeling approaches provide a way to analyze, plan, streamline, and control the structure and behavior of business processes. For instance, they can inform decision makers about undesirable events that are likely to happen in the future, giving the decision maker an opportunity to intervene. The talk introduces a new predictive modeling technique for business processes based on probabilistic finite automatons. Fitting such a probabilistic model to a data set of past behavior makes it possible to predict how currently running process instances will behave in the future. To clarify how this technique works and to facilitate its adoption, the talk also shows a way to visualize the probabilistic models. The effectiveness of the technique is assessed via an experimental evaluation with synthetic and real-world data. Finally, the talk reports on current applications of the technique in the areas of classic business process management, corporate communication and collaboration and the Internet of Things.

14:00-16:00, Alexander Felfernig

Title: Recommendation and Decision Technologies for Complex Products and Services

Abstract: Recommendation technologies are widely used for increasing the accessibility of large item assortments – application examples thereof are online platforms such as amazon.com or netflix.com. Although already widely used in industrial environments, there are still many challenges to be tackled to further increase the applicability of these technologies. Especially when providing recommenders for complex products and services such as financial services, electronic equipment, and software artefacts, understandability and manageability issues arise with regard to the underlying knowledge bases. In scenarios where groups of users are interacting with such systems, mechanisms have to be provided that assure fairness and consensus in the underlying decision process. Furthermore, knowledge about human decision making has to be taken into account when developing recommendation systems, for example, mechanisms have to be included that are able to counteract decision biases. Finally, recommendation technologies are not only used for recommending products and services but also act as key-enabling technologies for achieving persuasive goals. This talk will focus on a discussion of solutions that help to tackle the mentioned challenges and have already shown to be useful in industry. In this context, new research results in terms of algorithms and techniques will be presented. The talk will be concluded with an overview of major issues for future research.

16:00-18:00, Sabine Graf

Title: How to make educational information systems more adaptive, intelligent and personalized?

Abstract: Information systems are prevalent in our daily lives and research showed that making such systems more adaptive, intelligent and personalized by enabling them to automatically consider users’ current situations, characteristics and preferences and providing them with actionable information can make these systems more effective and easier to use. An important domain for such information systems is education. Although research showed that education works best when it is tailored to individual people’s needs, the information systems that are widely used by educational institutions (e.g., learning management systems such as Moodle) provide very limited to no personalization, adaptivity or intelligent support. Furthermore, while these systems typically gather and store huge amounts of data about how people use these systems, even with the advancements in data mining, business intelligence and decision support systems in recent years, in the educational sector, such data are rarely used to inform and benefit users (e.g., instructors, learners, etc.). This talk will discuss how educational information systems can be enhanced to provide adaptive recommendations, intelligent support and customized information to learners, instructors and educational institutions. More concretely, the talk will focus on how to detect and retrieve a variety of useful information from raw data as well as how to present such information to users, for example, through dashboards and visualizations, or in the form of adaptive interfaces, intelligent support and personalized recommendations, using techniques from different fields such as data mining, user modelling, data/knowledge analytics, recommender systems, decision support systems, business intelligence and others. Results and findings will be discussed, showing that such enhanced information systems allow to better support users such as learners, instructors and the administration of educational institutions. In addition, future research directions will be outlined, to continue addressing some of the prevalent challenges in blended and technology enhanced education, such as increasing learner performance, improving user satisfaction and providing the right information to the right person at the right time. Furthermore, potential opportunities to apply our research to other domains such as e-commerce, business, tourism, etc. will be discussed.

25. November 2016, Lakeside, Raum L 1.014

9:00-11.00, Christian Huemer

Title: Model-Driven ERP System Development

Abstract: In the discipline of accounting, the resource-event-agent (REA) ontology is a well accepted conceptual accounting framework to analyze the economic phenomena within and across enterprises. We used REA as a basis for developing a domain specific modeling language and corresponding tool support for ERP system development. Evidently, a model-driven approach requires transforming the REA-DSL artifacts to code. Thus, we developed the transformation of the REA-DSL to a relational database for an ERP system. This approach offers the advantage that a domain expert verifies the relevant data in an „accounting language“, whereas the IT expert is able to work with traditional data base structures.

In an alternative approach, we target the adaptation of an ERP system to specific company’s needs by configuration and customization which usually is cost-intensive and requires experts with specialized know-how. Therefore, we developed a model-driven approach that configures a generic ERP system to customer needs by means of models in order to provide a less costly solution. In the so-called REAlist approach, the REA business models serve as configuration information to be interpreted at run-time by the generic, domain-agnostic ERP engine.

This talk will first introduce the REA-DSL that provides the foundation for both approaches and will afterwards highlight the REA-DSL transformation to data base structures and elaborate in detail on the REAlist architecture. In order to demonstrate the future research portfolio, the presented work is further discussed in the context of Industrie 4.0 and will highlight open research challenges for horizontal and vertical integration of ERP systems in production processes.

11:00-13.00, Dietmar Jannach

Titel: Empfehlungssysteme – Mehr als smarte Algorithmen zur Matrixvervollständigung

Kurzfassung: Automatisierte Empfehlungen und Personalisierung sind heutzutage ein allgegenwärtiger Bestandteil unserer Nutzererfahrung sowohl im World Wide Web als auch in mobilen Apps. In der Informatikforschung wurden in diesem Umfeld in den letzten Jahren enorme Fortschritte gemacht. Die Aufgabe der entwickelten Algorithmen ist es zumeist, möglichst exakt vorherzusagen, wie relevant ein Produkt, ein Service oder allgemein ein Objekt für den einzelnen Benutzer ist. Das Empfehlungsproblem wird in diesen Arbeiten oft als Problem der Vervollständigung einer dünn besetzten Matrix aus Benutzern und Objekten betrachtet. In diesem Vortrag wird anhand aktueller Forschungsergebnisse darauf eingegangen, warum Algorithmen mit einer hohen Vorhersagegenauigkeit auf Vergangenheitsdaten nicht unbedingt diejenigen sind, die zu den nützlichsten Empfehlungen für die Benutzer in der Praxis führen. Ausgehend von diesen Erkenntnissen wird ein konzeptueller Rahmen vorgeschlagen, der von einer algorithmenorientierten Vorgehensweise zu einem interdisziplinären ziel- und nutzenorientierten Forschungsansatz führt.

14:00-16:00, Agnes Koschmider

Titel: Vorrausschauende Analysen für smarte Umgebungen

Kurzfassung: Trotz der heute zu beobachtenden Verbreitung von Sensoren in unterschiedlichsten Geräten und Umgebungen, die Daten für individuelle Objekte (Auto, Person, etc.) mit personenbezogenen Verhaltensprofilen sammeln, existieren zur Prädiktion individuellen Verhaltens überraschend wenige wissenschaftliche Ergebnisse und praktische Ansätze. Dabei hätten Anwendungen solcher Verfahren potentiell einen hohen wirtschaftlichen als auch sozialen Mehrwert. Denkt man beispielsweise an Smart Home Umgebungen zur Unterstützung der Heimpflege älterer Menschen, ließen sich z.B. individuelle Wahrscheinlichkeiten zum Wechsel in eine andere Pflegestufe innerhalb einer gewissen Zeit prognostizieren. Im Kontext von Connected Cars könnten durch Auswertung menschlichen Verhaltens individuelle Gefahrensituationen prognostiziert werden, die den Eingriff des Fahrers ins System erfordern. Existierende Forschungsarbeiten im Bereich prädiktive Verhaltensanalyse beschränken sich weitgehend auf strukturierte Prozesse, bei denen die Reihenfolge einzelner Aktivitäten vordefiniert ist und sich alle individuellen Objekte nach dem gleichen Prozessschema richten. Diese Vorbedingungen des strukturierten menschlichen Verhaltens trifft in smarten Umgebungen, bei denen Daten aus Sensoren gesammelt werden (wie Smart Home oder Connected Cars) nicht zu, hier sprechen wir von unstrukturierten Entscheidungsfindungsprozessen.

16:00-18:00, Thomas Setzer

Title: Robust Integration of Judgmental and Statistical Predictions in Forecasting Support Systems

Abstract: The accuracy of forecasting plays a pivotal role in enterprise decision making as forecasts usually form part of an IS on which business functions, such as marketing or resource planning depend. Today, forecasts are typically derived by expert judgment supported by model-based predictions that are provided within forecasting support systems (FSS). There is, however, evidence that this integration is often carried out poorly and the resulting predictions are regularly biased. In this talk, I propose an alternative forecast generation process that – in the spirit of crowd wisdom and forecast blending – combines individual model-based and judgmental forecasts ex-post to derive less biased and more robust predictions. The core of the combination method is the analytical derivation of the previously unknown bias–variance decomposition of a combination’s mean squared error (MSE). In our recent work we could derive this decomposition for an important class of linear combinations (weighting schemes) of individual forecasts, which allows for determining the weighting scheme with minimum expected MSE. Empirical results will be presented that show significantly lower MSE when applying the approach compared the judgmental forecasts or commonly used weighting schemes. The outlook of the talk will discuss a novel kind of debiasing support system. The system is aimed at a cognitive engineering of experts (to reduce bias over time) and avoiding high-impact errors introduced by adjusting originally sound judgmental expectations through the combination. Based on an expert’s error history, the system provides information on the bias suggested to drive the difference and prompts him/her for action and explanation in case of strong deviation between the combined forecast and his/her expectation.

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Dem Leben im All auf der Spur

Dr. Gerda Horneck | 30.11.2016 | 18:00 Uhr | HS 10


Die Geschichte unserer Biosphäre reicht mindestens 3,8 Milliarden Jahre zurück, wie Fossilienfunde im ältesten Sedimentgestein belegen. Seit dieser Zeit hat sich das Leben von einfachsten Mikroorganismen zu der heutigen Vielfalt und dem Artenreichtum entwickelt, und hat dabei die Erde selbst, vor allem ihre Atmosphäre und die Gesteine, entscheidend mitgeprägt. Noch wissen wir nicht, wie das Leben einst entstanden ist und ob die Erde in dieser Hinsicht ein Unikat im Universum ist oder ob Leben eher ein kosmisches Phänomen ist, das zwangläufig immer dann entsteht, wenn die entsprechenden Voraussetzungen erfüllt sind. Hierbei sind Masse und Energie eines Sternes wesentliche Größen, die das Ausmaß eines lebensfreundlichen „Grüngürtels“, der so genannten habitablen Zone, bestimmen. Mit Hilfe der Weltraumtechnologie sind wir nun in der Lage, die Suche nach Leben außerhalb der Erde auch wissenschaftlich anzugehen: mit Raumsonden erforschen wir unser Sonnensystem – hier sind vor allem unser Nachbarplanet Mars und die Monde Europa, Titan und Enceladus der Riesenplaneten im Mittelpunkt -, mit Weltraumteleskopen erkunden wir das Universum bis in weit entfernte Regionen, und schließlich wird der Mensch selbst aufbrechen, um den Weltraum zu erkunden und vielleicht sogar einmal zu besiedeln.

Gerda Horneck studierte Biologie und Mikrobiologie in Frankfurt/Main und begann unmittelbar nach Abschluss ihrer universitären Ausbildung mit der Arbeit im Bereich Weltraumforschung. Diese Tätigkeiten führten sie von der Univ. Frankfurt/Main (Arbeitsgruppe Weltraum-Biophysik) über einen Aufenthalt als Visiting Scientist an einer Klinik in La Jolla (Kalifornien) zum Deutschen Zentrum für Luft- und Raumfahrt Köln, wo sie ab 1981 zuerst die Gruppe Exobiologie und danach die Sektion für Strahlungsmedizin am Institut für Luftfahrtmedizin leitete. Von 1997 bis 2004 war Dr. Horneck als stellvertretende Direktorin dieses Instituts am DLR tätig. Seit 2004 fungiert sie als externe Beraterin des DLR.

Dr. Horneck lehrte u.a. an den Universitäten Frankfurt/Main, Kiew und Peking, als leitende Forscherin war sie mit einer Reihe von Experimenten an Weltraummissionen beteiligt (z.B. zum Überleben von Bakterien im All oder zur Zellregeneration nach Strahlungsschäden). Sie ist Trägerin mehrerer Auszeichnungen, so etwa des DLR Senior Scientist Award oder des Life Sciences Award der Internationalen Akademie der Astronautik. 2010 wurde – in Anerkennung ihrer Pionierarbeit im Bereich der bakteriellen Forschung in Weltraum- und stark strahlenden Umgebungen – ein neu entdecktes Bakterium nach Gerda Horneck benannt.

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Wege, Umwege, Irrwege zur Kanalkapazität : Zur Geschichte der Entwicklung hocheffizienter digitaler Übertragungsverfahren [Slides]

Prof. Johannes Huber | 20.06.2016 | 17:00 Uhr | Lakeside B04, B4.1.114


Mit der Entwicklung der Informationstheorie gelang C. E. Shannon, dessen 100. Geburtstag heuer im Mai durch zahlreiche Feiern gedacht wurde, bereits im Jahre 1948 der Beweis, dass mittels Codierverfahren auch über gestörte Übertragungskanäle prinzipiell eine fehlerfreie digitale Übertragung möglich ist, solange nicht versucht wird, mehr Daten zu übertragen als die Kapazität des Kanals zulässt. Dieses Kanalcodierungstheorem leitete eine breite Forschungstätigkeit auf dem Gebiet der Kanalcodierung ein. Dennoch wurden über viele Jahre trotz des Einsatzes anspruchsvollster mathematischer Methoden nur eher bescheidene Fortschritte erreicht und das Ziel, die informationstheoretische Kapazität von Übertragungskanälen in der Praxis nutzbar zu machen, galt viele Jahre als grundsätzlich unerreichbar. Erst durch die Zufallserfindung der sog. „Turbo-Codes“ kam 1993 neue Bewegung in das Gebiet und dabei stellt es sich heraus, dass die Entwicklung durch das wenig geeignete Optimierungsziel „Maximierung der Minimaldistanz“, das aber niemals hinterfragt worden war, in eine ungünstige Richtung gelenkt worden war. Schließlich erkannte McKay 1996, dass die bereits 1963 von R. Gallager vorgeschlagenen „Low Density Parity Check Codes“  von allen bisher bekannt gewordenen Ansätzen wohl der direkteste Weg nahe an die Kanalkapazität gewesen wäre. So war das Problem eigentlich bereits 33 Jahre lang weitgehend gelöst, ohne dass dies bemerkt worden war. Im Jahr 2007 stellte schließlich Erdal Arikan mit der Erfindung der Polar Codes einfache Codier- und Decodierverfahren vor, durch die für eine nach unendlich strebende Codewortlänge die Kanalkapazität mathematisch beweisbar erreicht wird. Wieder zeigte sich, dass mit den nahe verwandten Reed-Muller Codes infolge des falschen Optimierungskriteriums bereits 53 Jahre zuvor das Ziel nur knapp verfehlt worden war.

Im Vortrag wird ausgehend von der Shannon´schen Informationstheorie der Begriff Kanalkapazität eingeführt. Die Wissenschaftsgeschichte wird anhand von verschiedenen Lösungsansätzen nachgezeichnet und es werden die Hemmnisse, die dabei zu Irr- und Umwegen geführt haben, identifiziert. Ein Ausblick auf die aktuelle Forschung und offene Fragen schließt den Vortrag ab.



Johannes Huber studierte Elektrotechnik an der Technischen Universität München und erwarb 1977 das Diplom. Er wurde 1982 zur Dr.-Ing. promoviert und erhielt 1991 den Titel Dr.-Ing. habil. mit einer Monographie zur Trelliscodierung. Seit 1991 ist er Professor für Nachrichtentechnik und Leiter des Lehrstuhls für Informationsübertragung an der Friedrich-Alexander-Universität Erlangen-Nürnberg. Von 2007 bis 2009 war er Dekan der Technischen Fakultät.

In der Forschung ist Johannes Huber auf den Gebieten digitale Übertragung, Informations- und Codierungstheorie, codierte Modulation, Entzerrungs- und Detektionsverfahren, MIMO-Übertragungsverfahren, DSL etc. aktiv. Er hat zwei Monographien verfasst und ist Autor und Co-Autor von ca. 330 wissenschaftlichen Veröffentlichungen. In den Jahren 1988, 2000 und 2006 wurden Publikationen, die er verfasst bzw. mit verfasst hat, mit dem Preis der deutschen informationstechnischen Gesellschaft ausgezeichnet. 2004 erhielt er den Innovationspreis der Vodafone-Stiftung für Mobilfunk und in den Jahren 2003 und 2010 wurde ihm der EEEfCOM Innovationspreis verliehen.

Prof. Huber ist Fellow of the IEEE, Corresponding Fellow of the Royal Society of Edinburgh und ordentliches Mitglied der Bayerischen Akademie der Wissenschaften (BAdW). An der BAdW leitet er die Kommission „Forum Technologie“ und ist stellvertretender Sprecher der Sektion III: Naturwissenschaften, Mathematik, Technikwissenschaften.

Inzwischen sind 11 seiner ehemaligen Doktoranden selbst Professoren an namhaften Universitäten und Hochschulen.

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Embedded Device Security: Countering Side-Channel Analysis and Fault Attacks

Dr. Martin Schaffer | June 28, 2016 | 12:00 | E.1.42


Though cryptographic algorithms like AES are crypto-analytically secure, real implementations must at least be analyzed versus logical attacks like API misuse. Smart Cards and similar devices in addition face fault- and side channel analysis attacks. Such attacks exploit physical effects to manipulate the device or learn information about secret information. As these attacks are very critical, customers in the Smart Card world ask for third party evaluation (e.g. Common Criteria or EMVCo) to high assurance levels. If passed, a certificate is issued by a trusted party. With the rise of the IoT, physical attacks and the respective third-party witnessing of resistance soon get relevant there as well. This talk will give an overview of physical attacks and respective countermeasures in HW and SW. Moreover, it introduces how such devices are evaluated and certified and how much do attacks “cost”.

Dr. Schaffer studied computer science at Klagenfurt University and Swiss Federal Institute of Technology, focusing on security, privacy and cryptography. While conducting research in these fields, he received his PhD from Klagenfurt University. In 2001 he also worked for IBM Research Zurich Lab. 2008, Dr. Schaffer joined NXP Semiconductors where he held several positions in the security area over the last years, such as Security Architect and Cryptographer. Since 2014, Dr. Schaffer is Head of Security Maturity & Certification.

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Rückblick: Polynomial matrices – a brief overview [Slides]

Der Rückblick zum TEWI-Kolloquium von Dr. Stephan Alexander Weiss am 25.04.2016 beinhaltet die Folien:


Polynomial matrices can help to elegantly formulate many broadband multi-sensor / multi-channel processing problems, and represent a direct extension of well-established narrowband techniques which typically involve eigen- (EVD) and singular value decompositions (SVD) for optimisation. Polynomial matrix decompositions extend the utility of the EVD to polynomial parahermitian matrices, and this talk presents a brief overview of such polynomial matrices, characteristics of the polynomial EVD (PEVD) and iterative algorithms for its solution. The presentation concludes with some surprising results when applying the PEVD to subband coding and broadband beamforming.

WeissStephan Weiss is Head of the Centre for Signal and Image Processing at the University of Strathclyde. He obtained Dipl.-Ing. and PhD degrees in 1995 and 1998 from the Universities of Erlangen-Nuernberg and from the University of Strathclyde. Since then, he has been a member of academic staff at the Universities of Southampton (1999-2006) and Strathclyde (1998/99 and since 2006). With his team we works on adaptive, array and statistical signal processing problems with applications in acoustics & audio, communications and biomedical problems. He has been co-organiser of the European Signal Processing Conference (EUSIPCO) 2009 in Glasgow and a number of other events.

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Rückblick: Student-centered teaching patterns in the context of computational thinking problem solving processes [Video][Slides]

Der Rückblick zum TEWI-Kolloquium von Dr. Bernhard Standl-Gruber am 18.5.2016 beinhaltet die Videoaufzeichnung und die Folien:


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Successful learning can take place when the learner is addressed at all levels of learning instead of limiting teaching to knowledge transfer but also involving an emotional and skills level. Considering this as the student-centered approach, we designed, carried out and revised in practice computer science lessons in 9th grade classrooms. During these real classroom experiences we identified certain successful scenarios when such learning was effective. We subsequently transformed scenarios to a more abstract representation and obtained as a result 24 patterns, which uniformly describe how student-centered lessons in computer science can be carried out. The patterns don’t specify detailed instructions for the teacher but still hold all the information necessary to be coherent with the pedagogical approach in the context of computer science. Instead of providing a detailed description of lesson plans and exact scenarios, the patterns describe how different teaching procedures can be approached alongside the student-centered approach. The advantage of this representation is, that it leaves the freedom of individual implementation to the teacher. In order to prove the concept of the patterns four case studies in classrooms were carried out with the design-based research approach as driving force combined with mixed methods as questionnaires, classroom meetings, and audio recordings. Outcomes showed, that these patterns have impact on students’ perception of the teacher’s attitudes. Furthermore, we identified detailed aspects of students’ communication characteristics during problem solving processes. In a next step, these patterns were further applied during a research visit in the United States in the context of computational thinking problem solving tasks. Assuming that problem solving processes can be found in everyday occurrences, computational thinking problem solving skills affect everyone and should be part of a general knowledge every person should have these days. Therefore, we combined the patterns with computer science algorithms in the context of everyday life settings and designed lesson scenarios for four high school classes. These classroom activities were accompanied with the mixed research approach and case studies. First results of this study showed, that students improved required skills for computational problem solving.

standlBernhard Standl is a postdoctoral researcher and lecturer at the Faculty of Computer Science at the University of Vienna and computer science teacher at a secondary school in Vienna. After graduating from computer science and history studies with teacher certification, he finished in 2014 the PhD studies in computer science education at the University of Vienna in Austria and completed the thesis in the interdisciplinary field of computer science and education. Since 2008 he was part of computer science education and interdisciplinary, international projects. 2015 he stayed as Fulbright research fellow at Missouri State University in Springfield, MO where he carried out an individual research project named coThink – Computational Thinking. His research interests are focused on computer science education and technology enhanced learning at secondary school level and is interested in research for promoting computational thinking aimed at inspiring students for experiencing computer science as an exciting subject.

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